What is a Stone Calculator?
A stone calculator estimates the volume and weight of crushed stone, gravel, river rock, or decorative stone needed for a project. Stone is sold by the cubic yard or by the ton, so accurate calculations prevent both over-ordering and under-ordering. The calculator accounts for the area to be covered, the desired depth, and the density of the specific stone type.
Different types of stone have different densities and coverage rates. Crushed stone is denser and compacts more than river rock or decorative pebbles. Understanding these differences ensures you order the right amount for your specific application.
Stone Calculation Formulas
Stone Types & Densities
| Stone Type | Density (lb/cu ft) | Tons per cu yd |
|---|---|---|
| Crushed Limestone | 95–100 | 1.28–1.35 |
| Crushed Granite | 95–105 | 1.28–1.42 |
| Pea Gravel | 90–100 | 1.22–1.35 |
| River Rock | 85–95 | 1.15–1.28 |
| Lava Rock | 40–55 | 0.54–0.74 |
Worked Example
Cover a 20 ft × 10 ft area with 4 inches of crushed limestone (100 lb/cu ft):
Weight = 66.7 × 100 = 6,667 lbs = 3.33 tons
Frequently Asked Questions
How much stone do I need per square foot?
At a 2-inch depth, you need about 0.167 cu ft (17 lbs) per square foot. At 4 inches deep, about 0.333 cu ft (33 lbs) per square foot. These are approximate values for stone at 100 lb/cu ft.
How deep should landscape stone be?
For decorative ground cover, 2–3 inches is typical. For pathways, 3–4 inches is recommended. For driveways, 4–6 inches of compacted base stone is standard.
How many tons of stone in a dump truck?
A standard dump truck holds 10–14 tons of stone, depending on the truck size and the stone density. A tandem axle dump truck typically carries 12–14 tons.